A Three-Component Synthesis of Spiropyrrolines.

A rapid synthesis of medicinally important spiropyrrolines has been achieved by the reaction of 1,3-indanediones, benzaldehyde, and (1-azidovinyl)benzene under catalyst- and reagent-free conditions. This is the first report to synthesize diverse spiropyrroline compounds from readily available feedstock materials under metal-free conditions.

Access to C4-arylated benzoxazoles from 2-amidophenol through C-H activation.

A Pd-catalyzed aerobic approach to access C4-aryl benzoxazoles by tandem C-H ortho-arylation and acid-mediated annulation of 2-amidophenol has been presented. The directing potential of the -NHCOR group over the -OH group was exploited for selective arylation adjacent to the amide group. Deuterium labeling experiments suggest that palladation predominantly occurs adjacent to the -NHCOR group and is the key step during benzoxazole formation. One-pot hydrolysis of the resulting C4-arylated benzoxazole was also accomplished to access structurally challenging 3-aryl aminophenols for further applications.